By default is a VIRTUAL column, which means values in these columns are evaluated on-the-fly and do not take up any storage. To index a property within your JSON document, you first create a generated column.
On a very small dataset it's also not that important, but with larger datasets the right index will improve read performance a lot. MySQL doesn't have a way to index JSON documents directly, but there is an alternative: generated columns.Īs long as you don't use a WHERE condition or an ORDER BY clause on the JSON column, you don't need to worry about generated columns and indexing. $thing->save() Indexing and virtual columns It happens automatically since you've defined the $casts property in your model: // read You don't need to worry about serializing or encoding to JSON before saving the data.
To prove that the JSON encoded string is cast to an array, we can dump the $things->meta attribute of the last query: array:2 [▼Īs you would expect, type casting also works the other way around. $things = App\Models\Thing::whereJsonContains('meta->many', 'Wardrobe')->first() all things where the meta.many array contains Wardrobe $things = App\Models\Thing::where('meta->single', 'Gingerbread')->get() all things where the meta.single property matchs 'Gingerbread' $things = App\Models\Thing::select()->get() These are the SQL queries we used before translated to Eloquent: // all things It's up to you if you prefer work with an associative array or with an object of stdClass: 'array', In the App\Models\Thing class you define a caster for the JSON field. $table->foreignIdFor(\App\Models\User::class) The migration below describes the table we used before: id() With the $casts property on your Model you specify how you want to work with the decoded JSON in PHP. Eloquent has supported JSON columns since Laravel 5.7, which means it translates a human readable syntax to a grammar specific to MySQL or other database engines. Let's be honest, who writes raw SQL these days? Most likely you rely on some kind of abstraction layer to access your database. INSERT INTO things (user_id, meta) VALUES(100, ' | If you take a look at the INSERT statements below, you will notice that the values we insert into the meta fields look like strings. We also need some dummy data to play around with.
Mysql json compare free#
(Feel free to ignore the user_id field: it's just there to show that we can mix relational data and JSON objects in a single table.) CREATE TABLE things (Ĭreated_at DATETIME DEFAULT CURRENT_TIMESTAMP To understand what you can do with JSON columns, let's create a table with a meta JSON field and also a reference to an imaginary users table. This hybrid approach is not new - PostgreSQL has supported JSON since 2013. MySQL has had a built-in JSON column type since 5.7, and a lot of improvements have been introduced with the 8.0 release. But the truth is you don't need another database. But what if there is some parts of your data that does not fit into a relational model - data that does not follow a strict schema? You could opt for a NoSQL database like MongoDB, that is optimized for storing JSON-like documents.
MySQL, like any other relational database, is great at modelling data structures and making connections between them.
Mysql json compare how to#
Learn about JSON columns in MySQL and how to use them in Laravel.
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